Department of Animal Biotechnology, Konkuk University, Seoul, South Korea.
Int J Nanomedicine. 2013;8:2719-32. doi: 10.2147/IJN.S45174. Epub 2013 Jul 31.
Graphene is a single-atom thick, two-dimensional sheet of hexagonally arranged carbon atoms isolated from its three-dimensional parent material, graphite. One of the most common methods for preparation of graphene is chemical exfoliation of graphite using powerful oxidizing agents. Generally, graphene is synthesized through deoxygenation of graphene oxide (GO) by using hydrazine, which is one of the most widespread and strongest reducing agents. Due to the high toxicity of hydrazine, it is not a promising reducing agent in large-scale production of graphene; therefore, this study focused on a green or sustainable synthesis of graphene and the biocompatibility of graphene in primary mouse embryonic fibroblast cells (PMEFs).
Here, we demonstrated a simple, rapid, and green chemistry approach for the synthesis of reduced GO (rGO) from GO using triethylamine (TEA) as a reducing agent and stabilizing agent. The obtained TEA reduced GO (TEA-rGO) was characterized by ultraviolet (UV)-visible absorption spectroscopy, X-ray diffraction (XRD), particle size dynamic light scattering (DLS), scanning electron microscopy (SEM), Raman spectroscopy, and atomic force microscopy (AFM).
The transition of graphene oxide to graphene was confirmed by UV-visible spectroscopy. XRD and SEM were used to investigate the crystallinity of graphene and the surface morphologies of prepared graphene respectively. The formation of defects further supports the functionalization of graphene as indicated in the Raman spectrum of TEA-rGO. Surface morphology and the thickness of the GO and TEA-rGO were analyzed using AFM. The presented results suggest that TEA-rGO shows significantly more biocompatibility with PMEFs cells than GO.
This is the first report about using TEA as a reducing as well as a stabilizing agent for the preparation of biocompatible graphene. The proposed safe and green method offers substitute routes for large-scale production of graphene for several biomedical applications.
石墨烯是一种由六边形排列的碳原子组成的单层二维片状结构，从其三维母体材料石墨中分离出来。制备石墨烯最常用的方法之一是使用强氧化剂对石墨进行化学剥离。通常，石墨烯是通过使用水合肼将氧化石墨烯（GO）脱氧来合成的，水合肼是最广泛和最强的还原剂之一。由于水合肼的高毒性，它不是大规模生产石墨烯的理想还原剂；因此，本研究专注于绿色或可持续的石墨烯合成以及石墨烯在原代小鼠胚胎成纤维细胞（PMEFs）中的生物相容性。
在这里，我们展示了一种简单、快速、绿色的化学方法，使用三乙胺（TEA）作为还原剂和稳定剂，从 GO 合成还原氧化石墨烯（rGO）。通过紫外-可见吸收光谱、X 射线衍射（XRD）、粒径动态光散射（DLS）、扫描电子显微镜（SEM）、拉曼光谱和原子力显微镜（AFM）对所得到的 TEA 还原 GO（TEA-rGO）进行了表征。
通过紫外-可见光谱证实了氧化石墨烯向石墨烯的转变。XRD 和 SEM 分别用于研究石墨烯的结晶度和制备石墨烯的表面形貌。拉曼光谱中缺陷的形成进一步支持了石墨烯的功能化，表明 TEA-rGO 具有更高的生物相容性。使用 AFM 分析 GO 和 TEA-rGO 的表面形貌和厚度。所呈现的结果表明，TEA-rGO 与 PMEFs 细胞的生物相容性明显优于 GO。
这是首次报道使用 TEA 作为还原剂和稳定剂制备生物相容性石墨烯。所提出的安全绿色方法为大规模生产用于多种生物医学应用的石墨烯提供了替代途径。
